Zoology Publications from Victoria University of Wellington—Nos. 54 to 57
Description of New Zealand Specimens
Description of New Zealand Specimens
For proportional dimensions in percent of total length see Table 1.
Head depressed, eye rather large, and snout profile pointed; trunk moderately stout, the abdomen less inflated than shown in Plate 1, which was photographed when the specimen was thawed after deep-freezing and when the abdomen was partially filled with water; anterior half of trunk slightly depressed, flatter below than above, almost trihedral in cross-section owing to ventrolateral thickening of the body wall muscles on each side; posterior half of trunk slightly compressed; dorsal profile in front of the 1st dorsal smoothly and shallowly arched; caudal peduncle slightly flatter in transverse section below than above, with a low dermal keel ventrolaterally on each side extending from the level of the 2nd dorsal fin posteriorly on to the first quarter of the caudal axis (Plate 2); no precaudal pit above or below.
Dermal denticles (Fig. 1A) on sides of trunk rather closely packed, contiguous or only partly overlapping, large and rough to the touch, with essentially tridentate blades and rhomboidal bases; the central tooth of each blade much longer than the lateral teeth; in a few denticles of the 922 mm specimen and in many denticles of the 1082 mm specimen one or both of the lateral teeth are subdivided to give one or occasionally two additional teeth; outer surface of each blade with a high, spine-like median ridge extending the entire length of the blade, and a lower, less prominent ridge along each lateral margin.
Least fleshy interorbital distance 1.9 in head measured to 1st gill-opening; snout broad in contour but bluntly pointed at the snout tip; eye more than twice as long as high; spiracle large, placed slightly above eye and behind it by a distance equal to almost ¼ of horizontal diameter of eye; gill-openings almost vertical, slightly concave and in a horizontal series anterior to pectoral base; lengths of gill-openings subequal; interspaces between gill-openings subequal; nostrils slightly oblique, placed a little nearer tip of snout than mouth; each nostril subdivided into a circular anterolateral aperture and a larger ovoid medial aperture by the anterior and posterior nasal flaps; the anterior nasal flap is short and triangular, directed posteriorly, and external to the deeper and fleshy posterior flap; medial to the anterior nasal flap the anterior margin of the medial nasal aperture is strikingly extended posteriorly as a long, thin, tapered barbel projecting posteroventrally; this barbel (Fig. 1C) is denticle-covered to its tip, and when ad pressed to the lower surface of the head reaches almost or quite as far back as the angle of the mouth; mouth moderately broad and weakly arched; preoral clefts short, page 3
reaching less than 1/3 the distance from the angles of the mouth to the upper symphysis; posteriorly the clefts are continued by oblique furrows which extend about 1/5 of the distance between the angles of the mouth and the 1st gill-openings.
Teeth , similar in the two jaws, their shape as in Fig. 1B; teeth at the centre of mouth slightly smaller than those further laterally, and upper teeth generally smaller than lower; two or three rows of teeth visible in both jaws.
First dorsal fin large, triangular, its origin behind the level of the posterior corner of the pectoral fin by a distance equal to ½ the horizontal diameter of eye;page 4
Table 1. Cirrhigaleus barbifer, proportional dimensions in per cent of total lengthpage 5 page 6
posterior insertion of 1st dorsal base nearer to origin of pelvic than to axil of pectoral by a distance almost equal to horizontal diameter of eye; exposed origin of 1st dorsal spine midway along 1st dorsal base; exposed spine in the 922 mm specimen extends halfway along that part of 1st dorsal anterior margin distal to exposed spine origin, but tip of spine is obliquely truncated and may have been longer than it is now; in the 1082 mm specimen the spine is broken; spine smooth edged, subtriangular in cross-section, its posterior surface grooved lengthwise; 2nd dorsal fin subequal to 1st dorsal, its base longer, its height slightly shorter; origin of 2nd dorsal not well marked, a little anterior to posterior tips of pelvic fins; exposed origin of 2nd dorsal spine above posterior 1/3 of 2nd dorsal base; exposed spine in the 922 mm specimen reaches almost to 2nd dorsal apex, but its tip is slightly worn or eroded like that of 1st dorsal; in the 1082 mm specimen its tip reaches beyond second dorsal apex; shape of 2nd dorsal spine similar to 1st dorsal; caudal fin shape as in Fig. 1D, with no definite subterminal notch, though in the 922 mm specimen there is a weak indentation, perhaps due to injury, in the margin behind the tip of the caudal axis; pectoral fins moderately large, short and broad, originating just behind the 5th gill-openings; when adpressed to the side of the trunk so that their anterior margins are horizontal their tips reach almost or quite to midway between levels of origin of 1st dorsal base and exposed 1st dorsal spine; pelvic fins large, their outer, anterior corners somewhat obtuse, broadly rounded.
Colour: when fresh brownish-grey above, paler to almost white below; after preservation in alcohol steel-grey above, paler below; in the 922 mm specimen most of underside pale grey with some small, irregular areas of white mottling on the ventral surface, particularly under the head and around the mouth; in the 1082 mm specimen most of underside white except for grey mottling below snout tip; trailing margins of all fins white; axils of pectoral and pelvic fins white; nasal barbel grey in the 922 mm specimen, white in the 1082 mm specimen.
Vertebrae: radiographs of the vertebral column are shown in Plate 3; both specimens have exactly the same vertebral counts; of the 87 precaudal centra (counted to upper caudal fin origin) 51 are monospondylous and 36 are diplospondylous; the transition from monospondyly to diplospondyly is accepted as occurring above the posterior 1/3 of the pelvic fin base, where there is an abrupt decrease in the length of the centra; caudal centra (posterior to the upper caudal fin origin) number 28.